TV action man Bear Grylls has hit back at critics who slammed him for leaving his son alone on rocks in the sea.

This week the survival expert found himself the centre of controversy after putting his eldest child Jesse up for a training rescue mission - and even tweeted a photo of the 11-year-old surrounded by the waters in Abersoch, north Wales.

But writing in The Times newspaper, 41-year-old Grylls said the stunt had been carefully planned and argued that children needed to take more risks in life.

He said: "When we try to strip our kids' world of risk we do them a gross disservice. We teach them nothing about handling life.

"All children have a right to adventure... these moments allow children to get excited about the possibilities the world has to offer.

"They teach independence, initiative, self-reliance and resourcefulness: skills that will serve them for the rest of their lives

"None of this, of course, should come at the expense of safety."

Grylls - whose TV shows include Get Out Alive, The Island and Mission Survive - also said his son was wearing a life-jacket and was "safe at all times... and very happy".

He added: "Let's not deceive ourselves into thinking that removing risk makes our children 'safe'. It doesn't.

"Every adventure comes with risk. Otherwise it wouldn't be an adventure.

"Being vigilant and managing risk is not the same as wrapping your kids in cotton wool. It is about common sense.

"I believe it is fundamentally unfair to put children in a holding pen until they are 18.

"That's why I remain defiantly determined to provide my own children with opportunities to discover the world, as well as their own natural talents.

"I am determined to stand beside them on that journey. And yes, it can be dangerous."

Grylls faced a backlash from other Twitter users and criticism in the media following Thursday's exercise.

And he appears to have since deleted the image of Jesse from his Twitter profile.

Among those who voiced their unhappiness was lifeboat station manager Gareth Hughes - who said his crew were told about a "low key" training routine but were not aware a youngster was involved.

Mr Hughes told the Daily Post newspaper: "I certainly wouldn't put my young son on those rocks, and also it could encourage people to do the same which would be unfortunate."

An RNLI spokesman later added: "The RNLI has worked with Bear Grylls over a number of years and he has been a great ambassador, which we are very grateful for.

"Last Thursday, on their normal training evening, the crew at Abersoch agreed to carry out a joint exercise with Bear.

"The lifeboat was in close attendance, the boy was in sight at all times and wearing a life jacket."